1. Field of the Invention
This invention is directed to apparatus which uses supersonic jets to loosen soil and the like and to convey the loosened material by vacuum from the digging face. More particularly, the invention is directed to such apparatus suitable for excavating around underground services and other buried objects without damaging them.
2. Background Information
Mechanical equipment provides a rapid and economical means for excavating soil and the like. However, such equipment can damage underground services such as gas, water, and sewer lines, and electrical and telephone cables and conduits. Such damage is not only costly, but dangerous to workers and others in the vicinity. For example, reports indicate that a majority of the damage to underground gas lines which has resulted in personal injury or property damage was caused by large mechanical excavation equipment. Damage to utility lines typically occurs when the location of the line is not accurately known and the equipment operator hits the line while excavating. In "busy" soil where multiple utility lines are buried, the only existing safe way to excavate is by hand using shovels. This means of excavation is labor intensive, time consuming and costly. There obviously exists a need to develop a "soft excavation" system that could rapidly loosen and remove soil using a technique that would also minimize the potential of damaging the services being excavated.
It is therefore an object of the present invention to provide apparatus for excavating soil and the like which will minimize the possible damage to underground utility lines and other buried objects in the event of accidental contact.
It is another object of the invention to provide excavating apparatus which will reduce the health and safety hazards to workers and those in the vicinity.
It is yet another object of the invention to reduce the overall cost of small hole excavation.
It is still another object of the invention to minimize the disruption of service and traffic flow while excavating utility lines.
It is an additional object of the invention to provide such apparatus which can also be used economically to excavate other materials such as, for instance, sand, coal and gravel.